Such a hydraulic valve arrangement is, for example, known from DE 102 19 717 B3.
Such a valve arrangement is, for example, required to be able to control a hydraulic motor in two working directions. Such a motor can, for example lift a load or lower it in a controlled manner. With such a motor it is also possible to activate working elements of a hydraulically activated working machine. In connection with an excavator, for example, it is possible to lift or lower an excavator arm or to change the inclination of an excavator shovel in relation to the excavator arm. Another application is, for example, an industrial truck, which has a grab for picking up a load, for example a large paper roll, and another motor, which is suited to lift the load.
The compensation valve in the valve arrangement mentioned above is a so-called “post-compensated” compensation valve, which has the advantage that, in case of parallel activation of two or more valve arrangements of the kind mentioned in the introduction and an insufficient flow of hydraulic fluid, that is, an undersupply, it distributes the hydraulic fluid evenly on all valve arrangements. The fluid flow in each valve arrangement sinks in relation to the predetermined desired values, so that an automatic allocation of the fluid flow into individual part flows occurs. Also with different loads on the motors connected to the valve arrangements the relation between the individual motor movements will be maintained.